FIRST GRADE ADDITION & SUBTRACTION STRATEGY GUIDE

Shelley Gray’s

ADDITION & SUBTRACTION

STRATEGY GUIDE

FIRST GRADE

introduction Hi there! I’m Shelley Gray, and I want to challenge you to focus intensively on math facts this school year. Let’s stop seeing math facts as an isolated math unit, and begin integrating them wherever possible into our math and daily routines.

A solid understanding of math facts in early grades will help your students as they progress to later grades. Imagine how simple long division and multi-digit multiplication can be when the basic facts are already mastered?

Strategy vs. memorization When we think about mastery of the math facts, we tend to think about getting a quick answer. Automaticity is a goal. This means that students can solve a fact within 1-3 seconds, and just “know” the answer. But there is more to it!

We want to teach our students to be flexible thinkers when it comes to solving an equation. This means that they are able to manipulate the numbers in different ways in order to solve a problem. The steps that one student takes to solve a problem might be very different than the steps that another student takes. We want to celebrate this flexible thinking!

Math fact fluency should not be based on the ability to perform a memorized series of steps. It is so much more than that.

Big goals Throughout your math fact instruction and practice this year, try to keep three main words in mind when it comes to how your students are solving a problem or equation: EFFECTIVE, EFFICIENT, FLEXIBLE. Is the strategy effective and efficient (is it quick and works well)? Are they able to think flexibly with the numbers?

© Shelley Gray www.ShelleyGrayTeaching.com

How to use this guide This guide is intended as a reference guide for the various mental math strategies that are best-suited to your particular grade level.

It can be really confusing to teach math strategies. How do you integrate them? When do you move on to the next one? How do you differentiate to the different ability levels?

My hope is that this guide gives you a starting point for reinforcing the strategies. Begin with the first strategy, allow your students to master it, and then move along to the next one.

If you are not in our 30-Day Math Fact Challenge private Facebook group yet, be sure to join so that you collaborate with other teachers who have the same goals as you. Join here:https://www.facebook.com/groups/424672038022627/

© Shelley Gray www.ShelleyGrayTeaching.com

resources You do not need to purchase any resources to reinforce these strategies. You simply need a commitment to teaching and reinforcing them throughout the year.

However, if you would like a complete system to help you do this, here is a link to The First Grade Addition Station and the First Grade Subtraction Station, which will reinforce all of the strategies that are outlined in this guide. The entire Addition and Subtraction Station programs are self-paced so that students will move through the strategies as they feel ready.

Addition Station: https://www.teacherspayteachers.com/Product/The-Addition-Station-First-Grade-1781284

Subtraction Station: https://www.teacherspayteachers.com/Product/The-First-Grade-Subtraction-Station-2121690

What’s included?

QUICK REFERENCE CARDS

The Quick Reference Cards can be laminated and put on a ring for quick and easy reference to the strategies that are best suited for this grade level.

They can also be used for oral assessments. I highly recommend oral assessments to assess math strategy knowledge. When you SEE a student solve an equation, you get a far different perspective than you do when you simply mark a written solution.

Oral assessments enable you to see which facts/strategies a student struggles with, which ones are quicker than the rest, and which strategies are used to solve a problem.

Oral assessment is the assessment method that is used in all of my math stations. Although this might seem like a huge task, it only takes about 1-2 minutes, and many teachers report that it is their favorite part of using the stations.

If you would like to try oral assessments, you can use the Quick Reference Cards from the previous few pages as a guide. Look for the following:•  Is he using an effective strategy to solve the equation?•  Is his strategy efficient? (meaning that he can solve the equation in 1-3 seconds)•  Can you see flexibility in his thinking? (is he able to manipulate the numbers in a flexible

way to make the strategy work for him?)

In this strategy guide you will find Quick Reference Cards and a timed test for assessment.

TIMED TESTS

Timed tests do not work for every student. However, they can be useful to assess fact recall.

I’ve included a timed test sheet following the Quick Reference Cards.

IF you choose to use them in your classroom, here are some ideas for use:

•  Focus on self-improvement and self-growth over time rather than competition with classmates.

•  Do not force a student to perform a timed test if it causes stress to him/her.•  Have students perform the assessment once every 2 weeks to assess self-improvement.•  Only expect to see growth if fact practice is a regular part of the classroom routine.

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ADDITION PAGES 7-10

Plus 0

Example: 6+0=6

Any number plus 0 equals that number.

14+0=14

5+0=5

2+0=2

13+0=13

18+0=18

8+0=8

15+0=15

7+0=7

12+0=12

17+0=17

20+0=20

11+0=11

2+0=2

16+0=16

10+0=10

Sample Equations:

Plus 1

Example: For 6+1, think, “1 more than 6.”

Any number plus 1 is one more than that number.

5+1=6

15+1=16

10+1=11

1+1=2

7+1=8

19+1=20

6+1=7

2+1=3

16+1=17

12+1=13

3+1=4

14+1=15

17+1=18

4+1=5

18+1=19

Sample Equations:

Plus 2

Example: For 6+2, think, “2 more than 6.”

Any number plus 2 is two more than that number.

9+2=11

5+2=7

18+2=20

6+2=8

13+2=15

12+2=14

2+2=4

14+2=16

7+2=9

10+2=12

3+2=5

8+2=10

11+2=13

15+2=17

4+2=6

Sample Equations:

ADDITION STRATEGIES QUICK REFERENCE CARDS FOR FIRST

GRADE

www.ShelleyGrayTeaching.com

DOUBLES

Example: 6+6=12

Try to have your students memorize these facts.

Sample Equations:

DOUBLES PLUS ONE

Example: for 5+6, think, “double the 5 to make 10, and then add one more.”

The double plus one more

5+6=11

9+10=19

1+2=3

3+4=7

8+9=17

2+3=5

7+8=15

6+7=13

4+5=9

Sample Equations:

DOUBLES Plus 2

Example: for 5+7, think, “double the 5 to make 10, and then add two more.”

The double plus two more

3+5=8

7+9=16

6+8=14

1+3=4

4+6=10

8+10=18

2+4=6

5+7=12

Sample Equations:

Counting On

Example: For 6+3, think, “6…7, 8, 9.”

Start with the higher number and count up.

14+3=17

3+2=5

4+2=6

5+2=7

19+1=20

9+3=12

15+2=17

2+1=3

6+2=8

11+3=14

16+1=17

6+3=9

7+3=10

9+4=13

10+4=14

Sample Equations:

1+1=2

2+2=4

3+3=6

4+4=8

5+5=10

6+6=12

7+7=14

8+8=16

9+9=18

10+10=20

PLUS 10

Example: To solve 12+10, just add one to the tens place to make 22.

Add one to the tens place. Work with numbers to 100.

Sample Equations:

PLUS 9

Example: For 3+9, think, “3+10=13, and then one less is 12.”

Add 10 and then take away 1.

5+9=14

9+9=18

2+9=11

7+9=16

10+9=19

4+9=13

8+9=17

3+9=12

6+9=15

Sample Equations:

PLUS 8

Example: For 3+8, think, “3+10=13, and then two less is 11.”

Add 10 and then take away 2.

4+8=12

8+8=16

11+8=19

6+8=14

9+8=17

2+8=10

7+8=15

10+8=18

3+8=11

5+8=13

Sample Equations:

Making ten

Example: “What can you add to 6 to make 10?”

The addition facts that make 10

8+___=10

4+___=10

6+___=10

1+___=10

9+___=10

Sample Equations:

3+___=10

7+___=10

10+___=10

2+___=10

5+___=10

5+10=15

43+10=53

89+10=99

12+10=22

20+10=30

50+10=60

4+10=14

67+10=77

28+10=38

17+10=27

14+10=24

33+10=43

24+10=34

2+10=12

65+10=75

1+8=9

12+8=20

How many equations can you solve in 1 minute? ADDITION FACTS TO 20

4+4=___ 3+1=___ 14+3=___ 2+2=___ 3+4=___ 3+7=___ 4+2=___ 9+10=___ 10+10=___ 3+5=___

3+3=___ 17+3=___ 14+1=___ 5+7=___ 6+2=___ 3+8=___ 9+1=___ 10+10=___ 8+9=___ 2+8=___

8+8=___ 4+5=___ 3+3=___ 3+10=___ 1+1=___ 7+10=___ 6+6=___ 5+3=___ 9+9=___ 7+8=___

7+3=___ 2+1=___ 8+3=___ 10+1=___ 5+6=___ 12+2=___ 5+8=___ 19+1=___ 10+12=___ 4+10=___

9+2=___ 7+7=___ 6+4=___ 11+3=___ 4+8=___ 8+1=___ 8+8=___ 5+5=___ 8+2=___ 6+7=___

DATE: _______________________ Total: ________ My goal for next time: _______

How many equations can you solve in 1 minute? ADDITION FACTS TO 20

4+4=___ 3+1=___ 14+3=___ 2+2=___ 3+4=___ 3+7=___ 4+2=___ 9+10=___ 10+10=___ 3+5=___

3+3=___ 17+3=___ 14+1=___ 5+7=___ 6+2=___ 3+8=___ 9+1=___ 10+10=___ 8+9=___ 2+8=___

8+8=___ 4+5=___ 3+3=___ 3+10=___ 1+1=___ 7+10=___ 6+6=___ 5+3=___ 9+9=___ 7+8=___

7+3=___ 2+1=___ 8+3=___ 10+1=___ 5+6=___ 12+2=___ 5+8=___ 19+1=___ 10+12=___ 4+10=___

9+2=___ 7+7=___ 6+4=___ 11+3=___ 4+8=___ 8+1=___ 8+8=___ 5+5=___ 8+2=___ 6+7=___


SUBTRACTION PAGES 12-16

Properties of 0

Example: 5-0=5 and 5-5=0

A number subtract 0 equals that same number. A number subtract that same number equals 0.

10-10=0

4-0=4

7-7=0

17-17=0

9-0=9

10-0=10

8-0=8

2-2=0

20-0=20

11-11=0

6-6=0

16-0=16

14-14=0

6-0=6

5-5=0

Sample Equations:

Sample Equations: Sample Equations:

subtraction STRATEGIES QUICK REFERENCE CARDS FOR FIRST

GRADE

www.ShelleyGrayTeaching.com

One less

Example: For 8-1, think: “one less than 8.”

-1 means one less

9-1=8

12-1=11

7-1=6

17-1=16

14-1=13

13-1=12

15-1=14

3-1=2

18-1=17

10-1=9

4-1=3

11-1=10

20-1=19

16-1=15

6-1=5

Two less

Example: For 8-2, think: “two less than 8.”

-2 means two less

6-2=4

12-2=10

3-2=1

9-2=7

20-2=18

8-2=6

14-2=12

7-2=5

18-2=16

11-2=9

4-2=2

10-2=8

17-2=15

5-2=3

13-2=11


Using doubles

Example: 14-7 should look familiar because we know that 14 is the double of 7.

Use the doubles facts. Practice facts to 24.

14-7=7

6-3=3

24-12=12

16-8=8

20-10=10

22-11=11

8-4=4

18-9=9

12-6=6

4-2=2

10-5=5

2-1=1

Using combinations of 10

Example: For 10-2, think, “I know that 8 and 2 makes 10, so the difference is 8.”

Know the combinations that make 10, and use those to subtract.

10-0=10

10-1=9

10-2=8

10-3=7

10-4=6

10-5=5

10-6=4

10-7=3

10-8=2

10-9=1

10-10=0


Counting back

Example: For 8-3, think: “8…7, 6, 5”

Start with the big number and count back to subtract 1, 2, 3, or 4.

10-3=7

17-3=14

12-2=10

4-3=1

18-4=14

13-3=10

12-4=8

3-2=1

19-3=16

10-2=8

11-2=9

5-2=3

15-4=11

9-4=5

11-3=8

Think addition

Example: For 15-10, think: “What can I add to 10 to make 15?”

Use addition to solve a subtraction equation.

5-4=1

10-5=5

17-13=4

20-10=10

12-8=4

13-3=10

19-8=11

8-5=3

18-8=10

10-8=2

9-5=4

14-10=4

11-9=2

10-6=4

17-11=6


Subtract 9

Example: For 15-9, think: “15-10 is 5, and then add 1 to make 6.”

First subtract 10, and then add 1 to the difference.

17-9=8

11-9=2

15-9=6

20-9=11

13-9=4

14-9=5

19-9=10

12-9=3

18-9=9

10-9=1

16-9=7

Subtract 8

16-8=8

11-8=3

20-8=12

17-8=9

12-8=4

13-8=5

9-8=1

15-8=7

10-8=2

18-8=10

19-8=11

14-8=6


Decomposing to get to 10

Example: For 14-5, do 14-4 first to get to 10, then subtract 1 more to make 9.

Decompose the subtrahend to get to 10 first, then keep subtracting.

13-6=7

15-9=6

12-4=8

17-9=8

11-3=8

15-6=9

14-6=8

12-7=5

16-9=7

17-8=9

16-8=8

12-5=7

19-12=7

14-8=6

13-5=8

Subtract 10

Example: For 32-10, take one group of 10 away from 32 to make 22.

Take one group of 10 away. Work with numbers to 100.

34-10=24

15-10=5

29-10=19

48-10=38

56-10=46

73-10=63

52-10=42

12-10=2

87-10=77

23-10=13

20-10=10

68-10=58

88-10=78

45-10=35

92-10=82

Example: For 15-8, think: “15-10 is 5, and then add 2 to make 7.”

First subtract 10, and then add 2 to the difference.

Sample Equations:

Subtract multiples of 10

Example: For 40-20, think: “40 subtract 2 groups of 10 makes 20.”

Subtract multiples of 10 from another multiple of 10.

60-20=40

40-30=10

80-10=70

70-50=20

100-90=10

70-40=30

50-30=20

50-20=30

80-70=10

30-10=20

40-10=30

60-50=10

100-80=20

90-70=20

80-40=40

How many equations can you solve in 1 minute? Subtraction FACTS TO 20

4-2=___ 9-6=___ 6-2=___ 17-7=___ 12-6=___ 20-3=___ 2-1=___ 13-9=___ 10-3=___ 16-7=___

15-2=___ 12-5=___ 11-2=___ 4-1=___ 14-7=___ 18-9=___ 8-2=___ 15-5=___ 8-0=___ 16-4=___

5-3=___ 4-4=___ 8-5=___ 13-3=___ 9-9=___ 2-2=___ 11-4=___ 7-5=___ 12-10=___ 10-5=___

7-2=___ 17-4=___ 14-10=___ 16-8=___ 6-3=___ 20-10=___ 17-5=___ 11-7=___ 3-3=___ 7-3=___

14-3=___ 6-5=___ 10-7=___ 3-1=___ 13-10=___ 5-2=___ 12-2=___ 9-3=___ 15-10=___ 13-6=___


How many equations can you solve in 1 minute? Subtraction FACTS TO 20

4-2=___ 9-6=___ 6-2=___ 17-7=___ 12-6=___ 20-3=___ 2-1=___ 13-9=___ 10-3=___ 16-7=___

15-2=___ 12-5=___ 11-2=___ 4-1=___ 14-7=___ 18-9=___ 8-2=___ 15-5=___ 8-0=___ 16-4=___

5-3=___ 4-4=___ 8-5=___ 13-3=___ 9-9=___ 2-2=___ 11-4=___ 7-5=___ 12-10=___ 10-5=___

7-2=___ 17-4=___ 14-10=___ 16-8=___ 6-3=___ 20-10=___ 17-5=___ 11-7=___ 3-3=___ 7-3=___

14-3=___ 6-5=___ 10-7=___ 3-1=___ 13-10=___ 5-2=___ 12-2=___ 9-3=___ 15-10=___ 13-6=___


Additional resources Are you looking for more resources to reinforce these mental math strategies in your classroom? The resources below will reinforce the strategies that are outlined in this guide.

The addition station

https://www.teacherspayteachers.com/Product/The-Addition-Station-First-Grade-1781284

Addition strategies task cards

The subtraction station

https://www.teacherspayteachers.com/Product/The-First-Grade-Subtraction-Station-2121690

https://www.teacherspayteachers.com/Product/Addition-Strategies-Task-Cards-First-Grade-Bundle-Sums-to-20-3778137

FIRST GRADE ADDITION & SUBTRACTION STRATEGY GUIDE

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